Just a thought:

Move, adapt or die. When organisms challenged by climate change respond by adapting, they evolve. When they move, they often encounter distant cousins and hybridise with them, sometimes evolving new species. When they die, they leave a niche open for other species to migrate or adapt into, and a warming climate tends to open the way for more species rather than fewer. In the same Nature essay, Thomas wrote: ‘Global-diversity gradients dictate that more warm-adapted species are available to colonise new areas than cold-adapted species retreating from those areas as the climate warms.’

Throughout 3.8 billion years of evolution on Earth, the inexorable trend has been toward an ever greater variety of species. With the past two mass extinction events there were soon many more species alive after each catastrophe than there were before it.